Scorpion 7.5 with twin 150hp

BobLS · 24 November 2006, 10:41

Hi,
I'm thinking of purchasing this set up. Does anyone have this or has been on a scorpion 7.5 with twin 150s?
Any ideas on speeds too?
Thanks

Tony · 24 November 2006, 11:34

I have a Scorpion.....
you wont be dissapointed whatever you buy

MarkM · 24 November 2006, 13:08

I have a Scorpion 7.5 with 250 horses on the back and 2 x 150 is effectively only a bit more. Top speed is 98 km/hr. Scorpion is a superb boat. It is not the fastest RIB but very secure and safe in rough seas.

BobLS · 24 November 2006, 13:33

Thanks guys....I have another question, does 2 engines give the same top speed as one of equal power? eg 2*150 or 1*300?
Perhaps excelleration better but not top speed is my guess! ???

MarkM · 24 November 2006, 13:42

No, 2x150 is probably 275 at the most.

Tony · 24 November 2006, 13:50

Two engines is not faster than one, but the security of 2 engines is very appealing, also the handling is far better. If you went for Etec's it would keep the weight down, therefore not losing to much top end.

Cookee · 24 November 2006, 14:32

Quote:

Originally Posted by BobLS

Thanks guys....I have another question, does 2 engines give the same top speed as one of equal power? eg 2*150 or 1*300?
Perhaps excelleration better but not top speed is my guess! ???

As a rule of thumb you will lose around 30% or more using two engines, there is also the extra cost in servicing, the fuel consumption will be higher and they will cost quite a bit more to start with - the only real advantages to a twin engined boat are that of redundancy - ie if one breaks the other will get you home - and with modern engine reliability that is becoming less likely (but still worth it if you're in the middle of nowhere), and of course stabilty and manouvrability the you get from two engines.

I reckon you will need two 200's to replace one 300 to get better performance!

howe · 24 November 2006, 18:27

We have a Scorpion 7.5 with a 225 Optimax which I guess will give a similar performance. We have a 21 inch three bladed prop and top speed with half a tank is 55mph. You won't be disappointed with the Scorpion's performance.

Brambles · 24 November 2006, 18:51

Hi BobLS & welcome to the forum.

You can't go wrong with a Scorpion. However if you are buying new I would suggest you get a comparable cost for an 8.1m with singe engine. The extra length of the 8.1 really does make a difference!

Regards

Ian

FreeTrader · 26 November 2006, 17:50

The Scorp is a great choice. I drive an 8.5m with a 225 Opti, and we've been through some hellish stuff this season, and survived to tell the tale.

But there's many times when I've thought an extra engine would give great peace of mind. I guess a lot depends on how you're going to use the boat.

In most cases an engine failure just means dropping the hook over the side and waiting for a mate to pick you up, but if you're in a F8+ onshore gale you'd be glad of the extra engine.

Tomas · 27 November 2006, 12:38

I've got a 4.7 Searider with a single 50 Johnson. I chuckled at the "drop the hook await that mate" comment. Here, more than 100 yards offshore the bottom is 6000 feet away.

Old Joke:

Guy gets nervous at sea state and location out of sight of land: "Captain, how far from land are we?" Captain replies, "Oh, about two miles." "But Captain, I can't even see land, how could it be two miles away?" Captain looks at him and says, "Two miles away, straight down."

Many fishermen around here who are regularly out in it are running twins. The occurance of guys floating to the West for two weeks or more is too frequent. I'm stuck with a single on my Avon and even with Handheld, flares, gps and water bottles I tend not to do some things I would with twins. Of course, if they both share a common fuel supply and that goes bad, so much for reduncancy. I guess even with a common tank, twin filter/separators would probably place the risk very low.

All that said....I'm pining for a 5.58 Ribcraft with twin four strokes!

Tomas

codprawn · 27 November 2006, 12:48

You have to go a very long way off most of the British Isles to find deep water. Scotland and the West of Ireland are exceptions. From the Bristol Channel you have to go out about 350 miles to find really deep water. That's what makes it so dangerous around here - 3000 miles of Atlantic rollers being forced into a shallow funnel....

Tenerife is a very popular destination for British holidaymakers - I wonder how many of them who go out on boat trips there realise they are suddenly in 10,000 feet of water?

When we used to live by the Red Sea there was one location where the reef dropped off from 12' to 6000' - it was an amazing feeling swimming over the edge - felt like going over the side of a cliff.

Richard B · 28 November 2006, 21:47

Quote:

Originally Posted by howe

We have a Scorpion 7.5 with a 225 Optimax which... top speed with half a tank is 55mph.

I reckon there might be couple more mph's to be had from your rig

howe · 29 November 2006, 23:06

thanks, I should try to run with less fuel. It is quite low in the rev range so assume that there may be a bit more. I have seen some very high claimed speeds but assume they must be going downhill or something. Gavin